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PubMed1993

Exploring the DNA binding domain of gene V protein encoded by bacteriophage M13 with the aid of spin-labeled oligonucleotides in combination with 1H-NMR.

The DNA binding domain of the single-stranded DNA binding protein gene V protein encoded by the bacteriophage M13 was studied by means of 1H nuclear magnetic resonance, through use of a spin-labeled deoxytrinucleotide. The paramagnetic relaxation effects observed in the 1H-NMR spectrum of M13 GVP upon binding of the spin-labeled ligand were made manifest by means of 2D difference spectroscopy. In this way, a vast data reduction was accomplished which enabled us to check and extend the analysis of the 2D spectra carried out previously as well as to probe the DNA binding domain and its surroundings. The DNA binding domain is principally situated on two beta-loops. The major loop of the two is the so-called DNA binding loop (residues 16-28) of the protein where the residues which constitute one side of the beta-ladder (in particular, residues Ser20, Tyr26, and Leu28) are closest to the DNA spin-label. The other loop is part of the so-called dyad domain of the protein (residues 68-78), and mainly its residues at the tip are affected by the spin-label (in particular, Phe73). In addition, a part of the so-called complex domain of the protein (residues 44-51) which runs contiguous to the DNA binding loop is in close vicinity to the DNA. The NMR data imply that the DNA binding domain is divided over two monomeric units of the GVP dimer in which the DNA binding loop and the tip of the dyad loop are part of opposite monomers. The view of the GVP-ssDNA binding interaction which emerges from our data differs from previous molecular modeling proposals which were based on the GVP crystal structure (Brayer & McPherson, 1984; Hutchinson et al., 1990). These models implicate the involvement of one or two tyrosines (Tyr34, Tyr41) of the complex loop of the protein to participate in complex formation with ssDNA. In the NMR studies with the spin-labeled oligonucleotides, no indication of such interactions has been found. Other differences between the models and our NMR data are related to the structural differences found when solution and crystal structures are compared.

Amino Acid Sequence↗

PubMed1984

Diffusion of oxygen in water and hydrocarbons using an electron spin resonance spin-label technique.

The Smoluchowski equation for the bimolecular collision rate of dissolved oxygen molecules with spin labels yielded values for the diffusion constant of oxygen in water that are in agreement with the Stokes-Einstein equation (D infinity T/eta, where eta is the macroscopic viscosity) and with published values obtained by conventional methods. Heisenberg exchange at an interaction distance of 4.5 A occurs with a probability close to one for each encounter. In mixed hydrocarbons (olive oil, paraffin oils) and sec-butyl benzene, D infinity (T/eta)rho, where rho lies between 0.5 and 1. Oxygen diffuses in the hydrocarbons between 10 and 100 times more rapidly than predicted from the macroscopic viscosity. Similar results would be expected for diffusion of oxygen in model and biological membranes. Parallel measurements of rotational diffusion of the spin labels show little correlation with measurements of translational diffusion of oxygen. Dipolar interactions between spin labels and oxygen appear negligible except in the limit of highest viscosities.

Diffusion↗

PubMed1988

Estimation of the distance between the divalent cation binding site of des-1-41-light chain-activated bovine plasma protein C and a nitroxide spin label attached to the active-site serine residue.

The paramagnetic effect of Mn2+ on the electron paramagnetic resonance spectrum of a nitroxide spin label covalently attached to the active-site serine residue of des-1-41-light chain bovine plasma-activated protein C, and situated at a distance of approximately 1.2 nm from this amino acid, has been utilized to estimate the distance on the enzyme surface between the single Mn2+ site and the free electron of the spin label. This distance has been found to be approx. 1.12 nm. A significant paramagnetic effect of Mn2+ on the spectrum of this same nitroxide spin label bound to activated protein C (APC) has been found. However, in this case distance calculations are complicated by the existence of a multiplicity of Mn2+ sites on APC. If it is assumed that a single Mn2+ site is responsible for the paramagnetic effect on the spectrum of the spin label, the interelectron distance on APC would be approx. 0.90 nm.

Animals↗

PubMed2005

Calcium structural transition of human cardiac troponin C in reconstituted muscle fibres as studied by site-directed spin labelling.

The in situ structure of human cardiac troponin C (hcTnC) has been studied with site-directed, spin labelling, electron paramagnetic resonance (SDSL-EPR). Analysis of the in situ structures of hcTnC is essential for elucidating the molecular mechanism behind its Ca(2+)-sensitive regulation. We prepared two hcTnC mutants (C35S and C84S) containing one native cysteine residue (84 and 35, respectively) for spin labelling. The mutants were labelled with a methane thiosulfonate spin label (MTSSL) and the TnC was reconstituted into permeabilized muscle fibres. The mobility of Cys84-MTSSL changed markedly after addition of Ca2+, while that of the Cys35 residue did not change in the monomer state or in fibres. The rotational correlation time of Cys84-MTSSL decreased from 32ns to 13ns upon Ca(2+)-binding in the monomer state, whereas in fibres the spectrum of Cys84-MTSSL was resolved into mobile (16ns) and immobile (35ns) components and the addition of Ca2+ increased the immobile component. Moreover, the accessibility of Cys84-MTSSL to molecular oxygen increased slightly in the presence of Ca2+. These data suggest that Cys35 remains in the same location regardless of the addition of Ca2+, whereas Cys84 is located at the position that interacts with B and C helices of hcTnC and interacts with troponin I (TnI) at high concentrations of Ca2+. We determined the distances between Cys35 and Cys84 by measuring pulsed electron-electron double resonance spectra. The distances were 26.0 angstroms and 27.2 angstroms in the monomer state and in fibres, respectively, and the addition of Ca2+ decreased the distance to 23.2 angstroms in fibres but only slightly in the monomer state, showing that Ca2+ binding to the N-domain of hcTnC induced a larger structural change in muscle fibres than in the monomer state.

Adenosine Triphosphatases↗

PubMed1985

Spin-labeled erythrocyte membranes: direct identification of nitroxide-conjugated proteins.

The covalent incorporation of a spin-labeled analog of N-ethyl maleimide into erythrocyte membrane proteins has been monitored by electron paramagnetic resonance spectroscopy and the individually labeled proteins detected by immunoblotting techniques, using an anti-nitroxide antibody, following electrophoretic separation of the membrane components. Spin-label was primarily found in the high molecular weight bands (I and II) with no incorporation in proteins with molecular weights less than 35,000. Increasing the reaction time between the spin-label and ghosts altered both the observed labeling pattern and the epr spectra with an increase in the proportion of strongly-immobilized species.

Cyclic N-Oxides↗

PubMed1984

Regulation of enzymes by fatty acyl coenzyme A. Interactions of short and long chain spin-labeled acyl-CoA with the acetyl-CoA site on pig heart citrate synthase.

The binding of two similar spin-labeled fatty acyl-CoA analogues, one short chain, 6-doxyloctanoyl-CoA (S-(2-(5-carboxybutyl)-2-ethyl-4, 4-dimethyl-3-oxazolidinyl-N-oxyl)-CoA) and one long chain, 6-doxylstearoyl-CoA (S-(2-(5-carboxybutyl)-2-dodecyl-4, 4-dimethyl-3-oxazolidinyl-N-oxyl)-CoA) to pig heart citrate synthase (citrate oxaloacetate-lyase (pro-3S-CH2COO- leads to acetyl-CoA) EC 4.1.3.7) has been compared. The binding of the short chain analogue could be satisfactorily fit by a classical treatment (independent, noninteracting sites) with well defined stoichiometry: 2 mol of spin label bound per mol of dimeric enzyme. Binding of the long chain analogue was complex and in excess of 2 mol/dimer. Competitive binding experiments using either analogue in the presence of various nucleotides and substrates revealed differences in the binding of the long and short chain analogues. These additional studies, together with kinetic measurements, implied isosteric binding of acyl-CoA, ATP, NADPH, NADH, NADP+, acetyl-CoA, and partial isosteric binding of the long chain acyl-CoA. Binding of NADPH and NADP+ to the same form of the enzyme, perhaps through overlapping sites, was kinetically verified even though these nucleotides had differing effects on the binding of the spin-labeled analogues. Oxalacetate was shown to decrease the binding of the long chain analogue but to have no effect on the binding of the short chain. This result was supported by kinetic measurements. The competitive binding experiments with the long chain analogue suggested that its complex isotherm resulted from binding in two classes of sites, i.e. two cooperative nucleotide sites and other sites. An empirical mathematical model employing this rationale provided a satisfactory fit for the binding of fatty acyl-CoA to citrate synthase. A spin-labeled fatty acid which was not bound by the native enzyme was appreciably bound in the presence of additional palmitoyl-CoA. This binding might be identified with one of the two sets of binding sites proposed in the model. These and previous results on acyl-CoA binding were correlated with the properties of the CoA binding site defined crystallographically (Remington, S., Wiegand, G., and Huber, R. (1982) J. Mol. Biol. 158, 111-152).

Acetyl Coenzyme A↗

PubMed1995

Utility of a novel spin-labeled nucleotide in investigation of the substrate and effector sites of phosphoribulokinase.

The activated spin-label 3-(2-bromoacetamido)proxyl modifies the sulfur atom of phosphorothioate-containing AMP, ADP, and ATP analogs in a facile reaction that produces a new series of spin-labeled nucleotides. One of these products, adenosine 5'-O-(S-acetamidoproxyl 3-thiotriphosphate) (ATP gamma SAP), has been evaluated as a structural probe for Rhodobacter sphaeroides phosphoribulokinase (PRK). When incubated with affinity-purified enzyme that contains tightly bound substrate ATP, ATP gamma SAP binds noncooperatively to the allosteric site (n = 1; KD = 8 microM). Probe bound in this site is displaced (K1/2 = 100 microM) by the allosteric effector, NADH, at concentrations comparable to those required for enzyme activation (Ka = 133 microM). In the presence of NADH, when PRK's substrate site is vacant, ATP gamma SAP binds in a cooperative mode (Hill coefficient approximately 2.9; KD = 20 microM). In the absence of NADH, ATP gamma SAP mimics ATP by exhibiting nonequilibrium binding to PRK. The observations with phosphoribulokinase, together with the straightforward nature of the methodology documented for synthesis and isolation of this class of spin-labeled nucleotides, suggest that these analogs have potentially wide application as structural probes.

Adenosine Triphosphate↗

PubMed1976

Changes in the restriction of molecular rotational diffusion of water-soluble spin labels during fatty acid starvation of yeast.

Yeast mutants lacking fatty acid synthetase activity (fas-) die when deprived of saturated fatty acid under conditions which are otherwise growth-supporting. The spin label technique is used to show that restriction of molecular rotational diffusion of spin label molecules dissolved in aqueous zones increases several fold under conditions of fatty acid starvation while the apparent physical state of cellular hydrocarbon zones remains essentially unchanged. We focus attention on the cellular aqueous interior as the potential site of alteration under selective starvation conditions. Correspondences exist between restriction of molecular motion of water soluble spin labels dissolved in the cell and loss of cell viability. The correspondences to changes in the molecular motion of hydrocarbon soluble spin labels are much less or are not detectable.

Electron Spin Resonance Spectroscopy↗

PubMed2000

Oligonucleotide labeling: synthesis of a new spin-labeled 2'-deoxyguanosine analogue.

In order to achieve an EPR sensitive probe for DNA, 3-carboxy-Proxyl free radical was linked to O-6 of dG through a five-atoms-tether. The modified base was incorporated into a 30-mer ODN, then annealed to its complementary DNA strand. Hydrodynamic parameters show only a slight destabilization with respect to the equivalent unlabeled hybrid. EPR could monitor the hybrid formation showing a progressive enlargement of the upfield signal in passing from the labeled ss- to the ds-30-mer.

Cyclic N-Oxides↗

PubMed1999

Side chain mobility and ligand interactions of the G strand of tear lipocalins by site-directed spin labeling.

Side chain mobility, accessibility, and backbone motion were studied by site-directed spin labeling of sequential cysteine mutants of the G strand in tear lipocalins (TL). A nitroxide scan between residues 98 and 105 revealed the alternating periodicity of mobility and accessibility to NiEDDA and oxygen, characteristic of a beta-strand. Residue 99 was the most inaccessible to NiEDDA and oxygen. EPR spectra with the fast relaxing agent, K(3)Fe(CN)(6), exhibited two nitroxide populations for most residues. The motionally constrained population was relatively less accessible to K(3)Fe(CN)(6) because of dynamic tertiary contact, probably with side chain residues of adjacent strands. With increasing concentrations of sucrose, the spectral contribution of the immobile component was greater, indicating a larger population with tertiary contact. Increased concentrations of sucrose also resulted in a restriction of mobility of spin-labeled fatty acids which were bound within the TL cavity. The data suggest that sucrose enhanced ligand affinity by slowing the backbone motion of the lipocalin. The correlation time of an MTSL derivative (I) attached to F99C resulted in the lack of side chain motion and therefore reflects the overall rotation of the TL complex. The correlation time of F99C in tears (13.5 ns) was the same as that in buffer and indicates that TL exists as a dimer under native conditions. TL-spin-labeled ligand complexes have a shorter correlation time than the protein alone, indicating that the fatty acids are not rigidly anchored in the cavity, but move within the pocket. This segmental motion of the ligand was modulated by protein backbone fluctuations. Accessibility studies with oxygen and NiEDDA were performed to determine the orientation and depth of a series of fatty acid derivatives in the cavity of TL. Fatty acids are oriented with the hydrocarbon tail buried in the cavity and the carboxyl group oriented toward the mouth. In general, the mobility of the nitroxide varied according to position such that nitroxides near the mouth had greater mobility than those located deep in the cavity. Nitroxides positioned up to 16 carbon units from the hydrocarbon tail of the ligand are motionally restricted and inaccessible, indicating the cavity extends to at least this depth. EPR spectra obtained with and without sucrose showed that the intracavitary position of lauric acid in TL is similar to that in beta-lactoglobulin. However, unlike beta-lactoglobulin, TL binds 16-doxyl stearic acid, suggesting less steric hindrance and greater promiscuity for TL.

Amino Acid Sequence↗

PubMed1982

Interaction of spin-labeled local anesthetics with the sodium channel of squid axon membranes.

The effects of spin-labeled local anesthetics on sodium currents of internally perfused squid axons were studied using the voltage-clamp technique. Internal application (10 mum) of the most potent spin-labeled local anesthetic used in this study produced a small initial block of sodium currents. However, after sixty repetitive pulses (to + 80 mV) given at 1 Hz, the sodium currents were drastically reduced. In addition to this frequency-dependent phenomenon, the anesthetic effect on the sodium currents was also sensitive to the voltage of the pulses. Both the frequency- and voltage-dependent properties remained intact after removal of sodium inactivation with pronase. The recovery of sodium currents from this frequency-dependent anesthetic effect followed a single exponential curve with a surprisingly long time constant of about 10 min. Such a long recovery time, which is longer than any known sodium inactivation process, led us to suggest that the recovery process represents the dissociation of drug molecules from their binding sites. We have also found that increasing hydrophobic character of the homologues series of spin-labeled local anesthetics enhances the frequency- and voltage-dependent block of sodium currents. This effect strongly suggests that hydrophobic interaction is an integral component of the binding site. These probes with their selective effects on the sodium currents, are expected to be highly useful in studying the molecular structure of the sodium channels.

Action Potentials↗

PubMed1998

Recent advances in site-directed spin labeling of proteins.

Site-directed spin labeling of proteins is experiencing a phase of rapid technical evolution, application and evaluation. New strategies have been introduced for determining membrane protein topography, electrostatic potentials, the orientation of proteins at membrane surfaces and inter-residue distances. New applications include studies of beta strands, structure mapping using spin-spin interactions, domain motions in soluble proteins and extensive structural analysis of a number of membrane and soluble proteins.

Cell Membrane↗

PubMed1990

Saturation transfer electron spin resonance of Ca2(+)-ATPase covalently spin-labeled with beta-substituted vinyl ketone- and maleimide-nitroxide derivatives. Effects of segmental motion and labeling levels.

The Ca2(+)-ATPase in native sarcoplasmic reticulum membranes was selectively spin-labeled for saturation transfer electron spin resonance (ESR) studies by prelabeling with N-ethylmaleimide and by using low label/protein ratios. Results with the nitroxide derivative of the standard sulphydryl-modifying reagent, maleimide, were compared with a series of six novel nitroxide beta-substituted vinyl aryl ketone derivatives which differed (with two exceptions) in the substituent at the ketone position. The two exceptions had a different electron withdrawing group at the alpha-carbon, to enhance further the electrophilic character of the beta-carbon. Although differing in their reactivity, all the conjugated unsaturated ketone nitroxide derivatives displayed saturation transfer ESR spectra indicative of much slower motion than did the maleimide derivative. The saturation transfer ESR spectra of maleimide-labeled Ca2(+)-ATPase therefore most likely contain substantial contributions from segmental motion of the labeled group. The effects of the level of spin labeling were also investigated. With increasing degree of spin label incorporation, the linewidths of the conventional ESR spectrum progressively increased and the intensity of the saturation transfer spectrum dropped dramatically, as a result of increasing spin-spin interactions. The hyperfine splittings of the conventional spectrum and the outer lineheight ratios of the saturation transfer spectrum remained relatively unchanged. Extrapolation back to zero labeling level yielded comparable values for the effective rotational correlation times deduced from the saturation transfer spectrum intensities and from the lineheight ratios, for the vinyl ketone label. For the maleimide label the extrapolated values from the integral are significantly lower than those from the lineheight ratios, probably because of the segmental motion. Comparison is made of the effective rotational correlation time for the vinyl ketone label with the predictions of hydrodynamic models for the protein diffusion, in a discussion of the aggregation state of the Ca2(+)-ATPase in the native sarcoplasmic reticulum membrane. The implications for the study of protein rotational diffusion and segmental motion, and of the proximity relationships between labeled groups, using saturation transfer ESR spectroscopy are discussed.

Animals↗

PubMedDate not supplied

[Adsorption of spin-labeled flocculants on E. coli cells].

The interaction of intact E. coli cells with polymeric flocculants polyethylenimine and dextran was being studied by spin-labelling. The nitroxyl groups of spin-labelled polymers are reduced during formation of the adsorption layer on the cell surface. Some peculiarities of redox reactions between polymer macroradicals and units of the bacterial electron-transport chain were studied depending of temperature and flocculation regime. The course of the reduction of spin-labelled polymer radicals and characteristics of EPR spectra of the flocculant give evidence on the formation of a loose polymeric layer on the surface of E. coli cells.

Adsorption↗

PubMed1978

Spin-labeling of Escherichia coli membrane by enzymatic synthesis of phosphatidylglycerol and divalent cation-induced interaction of phosphatidylglycerol with membrane proteins.

Escherichia coli membrane particulate fraction has been spin-labeled by incubating with sn-glycerol-3-phosphate, CTP, palmitoyl CoA and 12-nitroxide stearoyl CoA. Incorporation of the spin-labeled acyl chain into phosphatidyl-glycerol was confirmed. ESR spectrum of the spin-labeled phosphatidylglycerol in E. coli membrane consisted at least of two components; one due to the labels undergoing rapid anisotropic motions and the other due to strongly immobilized labels (the overall splitting value, approx. 58 G). The relative intensity of the two components was dependent on the concentration of divalent cations. The immobilized component decreased on treatment of the membrane with EDTA and increased on addition of Mg2+ or Ca2+. The spectrum at 1 mM Mg2+ or Ca2+ consisted almost only of the immobilized component. Spin-labeled phosphatidylglycerol in total lipid membrane showed ESR spectrum due to mobile labels and the spectrum was not affected appreciably by the divalent cations. The results suggest the divalent cation-mediated interaction of phosphatidylglycerol with proteins in E. coli membrane. Phosphoenolpyruvate-dependent uptake of methyl-alpha-D-glucoside was markedly accelerated by Mg2+. Ca2+ was not effective for the enhancement. The divalent cation-induced interaction of phosphatidylglycerol with proteins was discussed in relation to the sugar transport.

Calcium↗

PubMed1983

[Spin labels in the analysis of Ca-ATPase in the sarcoplasmic reticulum of rabbit skeletal muscles in hypercholesteremia].

The method of electron paramagnetic resonance with spin-labeled maleimide was used to study variation of the structure of Ca-ATPase of the sarcoplasmic reticulum (SR) in rabbit skeletal muscles under long-term hypercholesterolemia (HC). The rate of the maleimide spin label binding with Ca-ATPase of the SR was decreased in HC, which correlated with a lesser access of spin-labeled thiol groups for potassium ferricyanide and sodium ascorbate. HC led to a considerable reduction in the lability and to enhancement of hydrophobia of the spin-labeled fragment of the enzyme. It is concluded that the disordered function of the SR Ca-pump is a consequence of structural changes in the Ca-ATPase molecule in HC.

Animals↗

PubMedDate not supplied

Synthesis and characterization of novel spin-labeled photoaffinity nonnucleoside analogues of ATP as structural and EPR probes for myosin.

Two new spin-labeled photoreactive nonnucleoside ATP analogues, 1-(4-azido-2-nitrophenyl)amino-3-(1-oxyl-2,2,5, 5-tetramethylpyrrolidinyl-3-carbamido)-2-propyl triphosphate (SL-NANTP) and 2-(4-azido-2-nitrophenyl)amino-2,2-(1-oxyl-2,2,6, 6-tetramethyl-4-piperidylidene)di(oxymethylene) ethyl triphosphate (SSL-NANTP), were synthesized and characterized. This study aims to develop a second generation of NANTP-based analogues containing immobile spin labels that can be used to monitor conformational changes in myosin during the contractile cycle of muscle. Previous studies have shown that both a photoaffinity nonnucleoside ATP analogue, 2-[(4-azido-2-nitrophenyl)amino] ethyl triphosphate (NANTP) [Nakamaye et al. (1985) Biochemistry 24, 5226-5235], and a photoaffinity ATP analogue, 3'(2')-O-4-[4-oxo-(4-amino-2,2,6, 6-tetramethyl-piperidino-1-oxyl)-4-benzoyl] benzoyl adenosine 5'-triphosphate (SL-Bz(2)ATP) [Wang et al. (1999) J. Muscle Res. Cell Motil. 20, 743-753], behave like ATP in their interactions with myosin. Remarkably, photolabeled myosin recovers all of its normal enzymatic properties after treatment with actin in the presence of MgATP [Luo et al. (1995) Biochemistry 34, 1978-1987]. For SL-NANTP, the spin label moiety is attached to NANTP via an aminomethyl side chain. In SSL-NANTP, attachment is via a restricted spiro ring. The two new probes interact with myosin subfragment-1 (S1) in a manner analogous to ATP, and after photoincorporation, labeled S1 recovers full activity after treatment with actin and MgATP. The electron paramagnetic resonance (EPR) spectrum resulting from S1 photolabeled with SL-NANTP shows a very high degree of probe mobility. However, the EPR spectrum of S1 photolabeled with SSL-NANTP shows that the probe is highly immobilized with respect to S1, constrained to move within a cone of angle 52 degrees (full-width, half-max). Unlike the parent, NANTP, which photolabels on the 23 kDa tryptic fragment of S1, SSL-NANTP photolabels on the 20 kDa fragment. Its highly immobile nature means that it is potentially a useful reporter group to monitor cross-bridge motion in muscle fibers.

Actins↗

PubMed1989

A novel spin-label for study of membrane protein rotational diffusion using saturation transfer electron spin resonance. Application to selectively labelled class I and class II-SH groups of the shark rectal gland Na+/K+-ATPase.

Na+/K+-ATPase in membranous preparations from the rectal gland of Squalus acanthias has been spin-labelled either on Class I -SH groups, which maintain overall ATPase activity, or on Class II -SH groups, for which only phosphorylation activity is preserved. Labelling of the Class I groups requires solubilization of the membranes and subsequent reconstitution by precipitation with Mn2+ in order to remove contaminating peripheral proteins, which are also labelled. Control experiments with preparations in which the Class II groups are labelled demonstrate that the mobility and aggregation state of the enzyme in the reconstituted membranes are similar to those in the native membrane. Both the conventional maleimide nitroxide derivative and a new benzoylvinyl nitroxide derivative have been used for the labelling. The segmental mobility of the labels and the overall rotational diffusion of the labelled protein have been investigated using saturation transfer ESR spectroscopy. The benzoylvinyl spin-label derivative offers particular advantages for the study of the protein rotational mobility in that the segmental mobility is considerably reduced relative to that observed with the maleimide derivative. This is especially the case for the Class I groups, where the maleimide label exhibits pronounced segmental mobility. Comparison of the results from the two labels indicates that the integral of the saturation-transfer spectrum is much more sensitive to segmental motion than are the diagnostic line-height ratios. This fact allows a better level of discrimination between the two types of motion. The results from the benzoylvinyl nitroxide-labelled Class I groups suggest that the Na+/K+-ATPase is probably present as an (alpha beta)2-diprotomer (or higher oligomer) in the native membrane.

Animals↗